Former independent prosecutor Ken Starr said Friday that if he were advising President Donald Trump, he'd warn him about the risks of speaking with special counsel Robert Mueller.

However, Starr told CNN's "New Day" that the president and Mueller must eventually meet face-to-face.

"I would advise him of the risks," said Starr, who served as independent counsel investigating President Bill Clinton over Whitewater and Monica Lewinsky. "You have to know your client and you have to know the facts, and I gather from the reports we're seeing is that his lawyers, the majority of them are saying, 'Mr. President, don't go there.'"

Starr acknowledged he doesn't know all the facts in Trump's case, but if he were advising him, he'd tell him "this is a risky process."

"We have two guilty pleas for false statements to the FBI," said Starr. "This is very serious business. This is not a press conference. So the risks are extraordinarily high."

He said his advice would be to "go forward" for a face-to-face meeting.

"I think, depending on what Bob Mueller knows, and we don't know what Bob Mueller knows, but depending on what he knows, he will want to talk to the president. If the president resists, Bob Mueller has subpoena power."

If the matter goes to litigation, "it is not a very attractive spectacle" for Trump, who would face a "huge risk" of being seen as fighting a special counsel who has been doing his job.

Starr pointed out that initially, Clinton refused his initial request to sit down for an interview, but as the then-president had cooperated otherwise, an arrangement was reached without the need for a subpoena.

"I think subpoenaing the president is not a last resort but almost a last resort out of the respect for the dignity of the presidency," said Starr. "You want to have a negotiated agreement. And I think that's what's going to happen."

Mueller could also agree to accepting written answers to questions, a step that is frequently done during litigation, said Starr. However, there is nothing to say that Mueller would agree to that, but he may also insist that Trump follow up the written questions with an in-person meeting, said Starr.

Former independent prosecutor Ken Starr said Friday that if he were advising President Donald Trump, he'd warn him about the risks of speaking with special counsel Robert Mueller.However, Starr told CNN's "New Day" that the president and Mueller must eventually meet...